The detectability of high-redshift Lyα emission lines prior to the reionization of the universe

article The detectability of high-redshift Lyα emission lines prior to the reionization of the universe published yes Zoltán Haiman author 7c006e8c-cc0d-11ee-8322-cb904ef76f36 For a source of Lyα radiation embedded in a neutral intergalactic medium (IGM) prior to the reionization epoch, the Lyα emission line is strongly suppressed by the intervening IGM. The damping wing of the so-called Gunn-Peterson trough can extend to the red side of the emission line and erase a significant fraction of the total line flux. However, the transmitted fraction increases with the size of the local cosmological H II region surrounding the source, and therefore with the ionizing luminosity and age of the source. Motivated by the recent discovery of a Lyα-emitting galaxy at a redshift z = 6.56 (Hu et al.), possibly prior to the reionization of the IGM, we revisit the effects of a neutral IGM on the Lyα emission line. We show that for faint sources with little or even no ionizing continuum, a sufficiently broad (Δv ≳ 300 km s^-1) emission line can still remain observable. In particular, the line detected by Hu et al. is consistent with a source embedded in a neutral IGM. We provide characterizations of the asymmetry and total transmitted flux of the Lyα line as functions of the ionizing emissivity of its source. We argue that a statistical sample of Lyα emitters extending beyond the reionization redshift can be a useful probe of reionization. American Astronomical Society2002 eng The Astrophysical Journal 0004-637X 1538-435710.1086/343101 5761L1-L4 yes Haiman Z. 2002. The detectability of high-redshift Lyα emission lines prior to the reionization of the universe. The Astrophysical Journal. 576(1), L1–L4. Haiman, Z. (2002). The detectability of high-redshift Lyα emission lines prior to the reionization of the universe. The Astrophysical Journal. American Astronomical Society. <a href="https://doi.org/10.1086/343101">https://doi.org/10.1086/343101</a> Z. Haiman, The Astrophysical Journal 576 (2002) L1–L4. Haiman Z. The detectability of high-redshift Lyα emission lines prior to the reionization of the universe. The Astrophysical Journal. 2002;576(1):L1-L4. doi:<a href="https://doi.org/10.1086/343101">10.1086/343101</a> Z. Haiman, “The detectability of high-redshift Lyα emission lines prior to the reionization of the universe,” The Astrophysical Journal, vol. 576, no. 1. American Astronomical Society, pp. L1–L4, 2002. Haiman, Zoltán. “The Detectability of High-Redshift Lyα Emission Lines Prior to the Reionization of the Universe.” The Astrophysical Journal. American Astronomical Society, 2002. <a href="https://doi.org/10.1086/343101">https://doi.org/10.1086/343101</a>. Haiman, Zoltán. “The Detectability of High-Redshift Lyα Emission Lines Prior to the Reionization of the Universe.” The Astrophysical Journal, vol. 576, no. 1, American Astronomical Society, 2002, pp. L1–4, doi:<a href="https://doi.org/10.1086/343101">10.1086/343101</a>. 177462024-09-06T09:34:46Z2024-09-26T14:51:17Z